Background

Question 1

What is the incidence of laryngeal cancer (LCX) in the United States?

Answer 1

∼12,000 cases/yr of LCX (∼20% of all H&N)

Question 2

What are the risk factors for developing LCX?

Answer 2

Smoking, alcohol use, and voice abuse

Question 3

What are the subsites of the larynx?

Answer 3

Supraglottic, glottic, and subglottic

Question 4

What is the incidence/distribution of LCX according to subsite?

Answer 4

Glottic: 69%

Supraglottic: 30%

Subglottic: 1%

Question 5

What % of premalignant lesions (leukoplakia/erythroplakia) progress to invasive laryngeal lesions?

Answer 5

20% of premalignant laryngeal lesions ultimately progress to invasive cancer (higher for erythroplakia than leukoplakia).

Question 6

What is the most common LCX histology?

Answer 6

Squamous cell carcinoma (SCC) makes up >95% of LCX. Other histologies include verrucous carcinoma (1%–2%), adenocarcinoma, lymphoma, chondrosarcoma, melanoma, carcinoid tumor, and adenoid cystic carcinoma.

Question 7

What are the subdivisions of the supraglottic larynx?

Answer 7

Supraglottic larynx: Epiglottis (suprahyoid and infrahyoid), AE folds, arytenoids, ventricles, and false vocal cords (FVCs)

Question 8

What are the subdivisions of the glottic larynx?

Answer 8

Subglottis: 0.5 cm below the TVCs to the 1st tracheal ring

Question 9

What are the nodal drainage pathways of the various laryngeal subsites?

Answer 9

Supraglottic: levels II–IV

Glottic: virtually no drainage

Subglottic: pretracheal and Delphian (level VI)

Question 10

What is the incidence of hypopharyngeal cancer (HPxC) in the United States?

Answer 10

There are ∼2,500 cases/yr.

Question 11

What is the median age at Dx for HPxC?

Answer 11

The median age at Dx is 60–65 yrs for HPxC.

Question 12

What are the subsites of the hypopharynx (HPX)?

Answer 12

Pyriform sinus

Postcricoid area

Posterior pharyngeal wall

(Mnemonic: “3 Ps”)

Question 13

What are the anatomic boundaries of the HPX?

Answer 13

The HPX spans from C4–6 or from the hyoid bone to the inf edge of the cricoid cartilage.

Question 14

What is the sex predilection for HPxC based on the different subsites?

Answer 14

The sex predilection is predominantly male for pyriform sinus and post pharynx primaries, but predominantly female for postcricoid area tumors.

Question 15

What are the classic risk factors for the development of HPxC?

Answer 15

Smoking, alcohol, betel nut consumption, nutritional deficiency (vitamin C, Fe [Fe deficiency is associated with 70% of postcricoid cancers in northern European women]), and prior Hx of H&N cancer

Question 16

Is nodal involvement common with HPxC?

Answer 16

Yes. Nodal involvement is common due to abundant submucosal lymphatic plexus drainage to the retropharyngeal nodes, cervical LNs, paratracheal LNs, paraesophageal nodes, and SCV nodes.

Question 17

What are the most commonly involved nodal stations in HPxC?

Answer 17

Levels II, III, and the retropharyngeal nodes are most commonly involved in HPxC. Level VI can also be involved and therefore should be covered when planning these cases for RT.

Question 18

What is the name for the most sup of the lat retropharyngeal nodes?

Answer 18

The most sup of the lat retropharyngeal nodes is the Node of Rouviere.

Question 19

What % of HPxC pts have nodal involvement at Dx?

Answer 19

∼75% overall have nodal involvement at Dx (∼60% for T1).

Question 20

What is the typical histology seen in HPxC?

Answer 20

The predominant histology is SCC (>95%) → adenoid cystic, lymphoma, and sarcoma.

Question 21

What are the most common subsites of origin for HPxC?

Answer 21

The pyriform sinus (70%–80%), post pharyngeal wall (15%–20%), and postcricoid (5%) are the most common subsites of origin.

Question 22

At what cervical spine levels are the hyoid bone and the TVCs located?

Answer 22

The hyoid bone is at C3, whereas the TVCs are located near C5–6.

Question 23

The subglottic space extends from

Answer 23

the first tracheal ring to
5 mm inferior to the free edge true vocal cords (TVCs)

Question 24

The glottic larynx contains

Answer 24

the true vocal folds, anterior
commissure, posterior commissure, and the infraglottic
space (5 mm inferior to the free edge of the TVCs)

Question 25

The supraglottic larynx contains

Answer 25

: ventricles, false vocal folds (FVCs), aryepiglottic folds, and epiglottis (infrahyoid, suprahyoid,
laryngeal surface, lingual surface).

Question 26

medialized fixed cord is caused by

Answer 26

recurrent laryngeal
nerve injury

Question 27

a lateralized fixed cord or hypomobile is
caused by

Answer 27

injury of intrinsic laryngeal muscles.
Lateralized fixed/hypomobile TVCs are often seen with
laryngeal cancer.

Question 28

pre-epiglottic space is

Answer 28

anterior to the epiglottis and superior to the vocal
folds. It is contiguous with the paraglottic space and base of tongue. bounded by the mucosal surface
of the vallecula superiorly, hyoid/thyroid strap muscles
anteriorly, and root of the epiglottis posteriorly and inferiorly communicates with the paraglottic spaces.

Question 29

The paraglottic space is

Answer 29

a small fat
plane adjacent to the thryoid cartilage. The paraglottic and pre-epiglottic spaces are connected
fat planes. The paraglottic space is bounded by the thyroid cartilage laterally and the TVCs, FVCs medially. Laryngeal cancer often invades the paraglottic and preepiglottic spaces. There are no barriers to spread to the
adjacent space if one is involved

Question 30

FVCs can be distinguished
from the TVCs because

Answer 30

FVCs have a band of fatty tissue and the
TVCs do not